DALLAS (AP) – A man who has served 27 years in prison for aggravated sexual assault is due to become the latest person exonerated through DNA testing in Dallas County.

District Attorney Craig Watkins announced Wednesday that 55-year-old Johnny Pinchback has been cleared as a result of forensic testing conducted last year.

Watkins says prosecutors will ask for a favorable ruling on Pinchback’s innocence at a writ hearing Thursday.

Pinchback was sentenced to 99 years in prison in October 1984 after he was convicted of raping two girls, both under 16, as they were walking home from school.

He was exonerated after an investigation was launched in 2009 by the Innocence Project of Texas.

He will be the 22nd person cleared by DNA evidence in Dallas County since 2001.

(© Copyright 2011 The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed.)